单复句子互换This is my brother This is his cousinThese are ID card
单复句子互换
This is my brother
This is his cousin
These are ID card
Those are baseballs
Is yhis your faher?
X-[y-2x-(x-y)}
2(a²b-3ab²)-3(2a²b-7ab²)
一直m²与-2n²的和为A,1+n²与-2m²的差为B,求2A-4B
先化简再求值:4X²Y-{6xy-3(4xy-2)-x²y}+1其中x=2,y=二分之一
由于看错了符号,某学生把一个多项式减去x²+6x-6误当成了加法计算,结果得到2x²-2x+3,正确的结果应该是多少?